Very little is known about this moss. Like all mosses, it reproduces by spores instead of seeds, although mature spore capsules have not been observed in the wild in Britain.
The small, rough-textured mats formed by this moss can vary in colour from a yellowish-green to pale green. Its main stems, which adhere to the underlying rock on which it grows, reach 40 mm in length. From these arise numerous crowded branches, only three to eight millimetres long. These, too, are sometimes subdivided into yet smaller branches. The slender, triangular leaves grow close to the stem, overlapping one another. They are usually flat and finely toothed or they can be un-toothed. Initially thought to be a species in the genus Eurhynchium, its capsules, with their combination of conical lids and knobbly stems led scientists to place it in the closely related Brachythecium genus as a previously undescribed species. However, it has now been proven to belong to the genus Scleropodium instead.
Mrs. Appleyard's moss was thought to be endemic to Britain, and known from one site in Somerset, one in Wiltshire and six in Derbyshire. It has now also been discovered in Ireland and north-western Germany, and more new sites will probably be discovered.